Re: [PATCH v2 0/2] Add a watchdog driver that uses ARM Secure Monitor Calls.

[Florian Fainelli]

On 4/15/2020 5:56 PM, Julius Werner wrote:
> > Can anyone provide advice about making SMCWD_FUNC_ID a device tree
> > param directly, vs using the compatible to select from a table.
>
> Sounds like most people prefer the way with using different compatible
> strings? (Personally I don't really care either way.)

The PSCI binding itself has provision for specifying function IDs for 
different functions, and this seems to be followed by other subsystems 
as well like SCMI:

https://www.spinics.net/lists/arm-kernel/msg791270.html

I could easily imagine that a firmware would provide two functions IDs 
(one for AArch32, one for AArch64) and that it could change those over 
time while not changing the compatible string at all.
--
Florian